Bulkhead planning · Guide 1 of 5 · 5 min readUpdated
Measure and plan a basement bulkhead
Set a reliable floor and ceiling reference, model one- or two-face runs, and check the finished enclosure before choosing material quantities.
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Measure the complete obstruction
In Room & ceiling, enter the room width and depth and the Ceiling reference height measured from the proposed finished floor to the underside of the structure supporting the enclosure. Include the planned floor buildup before entering that height.
Obstruction width and Drop below ceiling describe everything inside the box: duct insulation, hangers, fittings, beams or pipework. Measure several points along the run and use an envelope that contains the widest and lowest parts. A changing profile may need separate straight runs.
Enter the required side and bottom clearances separately. The example one-inch gaps are editable planning values, not equipment requirements. Keep access routes for valves, cleanouts, dampers and electrical junctions in the layout.
Choose one face or two
| Mounting | What the planner encloses |
|---|---|
| Across room · two faces | Two side frames and an underside. The obstruction is centred between the faces. |
| Along a wall · one face | An outer frame and underside meeting a wall. Obstruction width is measured from that wall to the farthest obstruction edge. |
Support the enclosure from suitable building framing. A duct or pipe is not the bulkhead’s support.
Place straight runs in the room
Framing length is the length of the frame. Closing a start or far end adds one drywall thickness beyond that frame. At a closed end, the obstruction model stops short to leave room for the entered framing depth and side clearance; confirm the real service ends there.
Left offset and Top offset locate the finished box from the room’s top-left corner. Run direction chooses the room-width or room-depth axis. For wall runs, the wall lies on the top side of a width run or the left side of a depth run. The tool does not detect actual walls.
Add up to 12 runs, then select them from Edit run or Room plan. Finished boxes must stay inside the room and cannot overlap. Runs may meet edge-to-edge, but an L- or T-junction does not become one combined frame automatically; shared framing, drywall and corner details need review.
Read the finished envelope
Finished width includes the side framing and side drywall. Finished drop includes the obstruction, bottom clearance, selected bottom framing and underside drywall. Clear below measures from the finished floor to the underside of that drywall.
Example: a 24-inch-wide obstruction dropping 10 inches, two wood 2×3 side frames, one-inch clearances, flush 1½-inch-deep crosspieces and ½-inch drywall produce a 32-inch finished width and 13-inch finished drop. From a 96-inch ceiling reference, the clear height is 83 inches, or 6 ft 11 in.
Clear below = ceiling reference height − finished bulkhead drop
Headroom is a dimension, not an automatic compliance check. Check the requirements for the actual room, route and project before fixing its height.
Review the section, then the room
Section shows the space around the obstruction. Room plan checks position and adjacent runs. In 3D detail, Show framing & obstruction reveals the frame; turning it off shows the finished box. Drag to orbit and use Fit view after changing dimensions.
Framing material, Bottom framing position, spacing and finish settings apply to every run in this project. Run dimensions, location, clearances, mounting and end caps are individual. Correct any layout error before relying on the drawings or quantities.